The daughter of Colonel George Barney (at one stage the New South Wales Surveyor-General and member of the Legislative Council, who led the settlement attempt at Port Curtis, Gladstone), Maria Scott accompanied her parents back to England in May 1844, but soon returned with them to Australia. She married David Charles Frederick Scott, a cousin of David Mitchell, founder of the Mitchel Library, where the Scott family papers are held.
She was a pupil of Conrad Martens before her marriage, and is best known for her pencil drawings. Her first exhibition was in 1854, and her watercolours were awarded a medal at the 1862 London International Exhibition.
Her novels predominantly feature orphans or stolen children, villainous adults defrauding them of their inheritance, and saintly young people dying. The Dictionary of Australian Artists (1992) suggests that her moral romances were probably written as 'an escape from the desolation she felt at the death' of her last surviving child in 1987.